1 // SPDX-License-Identifier: (GPL-2.0 OR MIT)
2 //
3 // Copyright (c) 2018 BayLibre, SAS.
4 // Author: Jerome Brunet <jbrunet@baylibre.com>
5
6 #include <linux/clk.h>
7 #include <linux/module.h>
8 #include <linux/of_irq.h>
9 #include <linux/of_platform.h>
10 #include <linux/regmap.h>
11 #include <sound/soc.h>
12 #include <sound/soc-dai.h>
13 #include <sound/pcm_params.h>
14
15 #define PDM_CTRL 0x00
16 #define PDM_CTRL_EN BIT(31)
17 #define PDM_CTRL_OUT_MODE BIT(29)
18 #define PDM_CTRL_BYPASS_MODE BIT(28)
19 #define PDM_CTRL_RST_FIFO BIT(16)
20 #define PDM_CTRL_CHAN_RSTN_MASK GENMASK(15, 8)
21 #define PDM_CTRL_CHAN_RSTN(x) ((x) << 8)
22 #define PDM_CTRL_CHAN_EN_MASK GENMASK(7, 0)
23 #define PDM_CTRL_CHAN_EN(x) ((x) << 0)
24 #define PDM_HCIC_CTRL1 0x04
25 #define PDM_FILTER_EN BIT(31)
26 #define PDM_HCIC_CTRL1_GAIN_SFT_MASK GENMASK(29, 24)
27 #define PDM_HCIC_CTRL1_GAIN_SFT(x) ((x) << 24)
28 #define PDM_HCIC_CTRL1_GAIN_MULT_MASK GENMASK(23, 16)
29 #define PDM_HCIC_CTRL1_GAIN_MULT(x) ((x) << 16)
30 #define PDM_HCIC_CTRL1_DSR_MASK GENMASK(8, 4)
31 #define PDM_HCIC_CTRL1_DSR(x) ((x) << 4)
32 #define PDM_HCIC_CTRL1_STAGE_NUM_MASK GENMASK(3, 0)
33 #define PDM_HCIC_CTRL1_STAGE_NUM(x) ((x) << 0)
34 #define PDM_HCIC_CTRL2 0x08
35 #define PDM_F1_CTRL 0x0c
36 #define PDM_LPF_ROUND_MODE_MASK GENMASK(17, 16)
37 #define PDM_LPF_ROUND_MODE(x) ((x) << 16)
38 #define PDM_LPF_DSR_MASK GENMASK(15, 12)
39 #define PDM_LPF_DSR(x) ((x) << 12)
40 #define PDM_LPF_STAGE_NUM_MASK GENMASK(8, 0)
41 #define PDM_LPF_STAGE_NUM(x) ((x) << 0)
42 #define PDM_LPF_MAX_STAGE 336
43 #define PDM_LPF_NUM 3
44 #define PDM_F2_CTRL 0x10
45 #define PDM_F3_CTRL 0x14
46 #define PDM_HPF_CTRL 0x18
47 #define PDM_HPF_SFT_STEPS_MASK GENMASK(20, 16)
48 #define PDM_HPF_SFT_STEPS(x) ((x) << 16)
49 #define PDM_HPF_OUT_FACTOR_MASK GENMASK(15, 0)
50 #define PDM_HPF_OUT_FACTOR(x) ((x) << 0)
51 #define PDM_CHAN_CTRL 0x1c
52 #define PDM_CHAN_CTRL_POINTER_WIDTH 8
53 #define PDM_CHAN_CTRL_POINTER_MAX ((1 << PDM_CHAN_CTRL_POINTER_WIDTH) - 1)
54 #define PDM_CHAN_CTRL_NUM 4
55 #define PDM_CHAN_CTRL1 0x20
56 #define PDM_COEFF_ADDR 0x24
57 #define PDM_COEFF_DATA 0x28
58 #define PDM_CLKG_CTRL 0x2c
59 #define PDM_STS 0x30
60
61 struct axg_pdm_lpf {
62 unsigned int ds;
63 unsigned int round_mode;
64 const unsigned int *tap;
65 unsigned int tap_num;
66 };
67
68 struct axg_pdm_hcic {
69 unsigned int shift;
70 unsigned int mult;
71 unsigned int steps;
72 unsigned int ds;
73 };
74
75 struct axg_pdm_hpf {
76 unsigned int out_factor;
77 unsigned int steps;
78 };
79
80 struct axg_pdm_filters {
81 struct axg_pdm_hcic hcic;
82 struct axg_pdm_hpf hpf;
83 struct axg_pdm_lpf lpf[PDM_LPF_NUM];
84 };
85
86 struct axg_pdm_cfg {
87 const struct axg_pdm_filters *filters;
88 unsigned int sys_rate;
89 };
90
91 struct axg_pdm {
92 const struct axg_pdm_cfg *cfg;
93 struct regmap *map;
94 struct clk *dclk;
95 struct clk *sysclk;
96 struct clk *pclk;
97 };
98
axg_pdm_enable(struct regmap * map)99 static void axg_pdm_enable(struct regmap *map)
100 {
101 /* Reset AFIFO */
102 regmap_update_bits(map, PDM_CTRL, PDM_CTRL_RST_FIFO, PDM_CTRL_RST_FIFO);
103 regmap_update_bits(map, PDM_CTRL, PDM_CTRL_RST_FIFO, 0);
104
105 /* Enable PDM */
106 regmap_update_bits(map, PDM_CTRL, PDM_CTRL_EN, PDM_CTRL_EN);
107 }
108
axg_pdm_disable(struct regmap * map)109 static void axg_pdm_disable(struct regmap *map)
110 {
111 regmap_update_bits(map, PDM_CTRL, PDM_CTRL_EN, 0);
112 }
113
axg_pdm_filters_enable(struct regmap * map,bool enable)114 static void axg_pdm_filters_enable(struct regmap *map, bool enable)
115 {
116 unsigned int val = enable ? PDM_FILTER_EN : 0;
117
118 regmap_update_bits(map, PDM_HCIC_CTRL1, PDM_FILTER_EN, val);
119 regmap_update_bits(map, PDM_F1_CTRL, PDM_FILTER_EN, val);
120 regmap_update_bits(map, PDM_F2_CTRL, PDM_FILTER_EN, val);
121 regmap_update_bits(map, PDM_F3_CTRL, PDM_FILTER_EN, val);
122 regmap_update_bits(map, PDM_HPF_CTRL, PDM_FILTER_EN, val);
123 }
124
axg_pdm_trigger(struct snd_pcm_substream * substream,int cmd,struct snd_soc_dai * dai)125 static int axg_pdm_trigger(struct snd_pcm_substream *substream, int cmd,
126 struct snd_soc_dai *dai)
127 {
128 struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);
129
130 switch (cmd) {
131 case SNDRV_PCM_TRIGGER_START:
132 case SNDRV_PCM_TRIGGER_RESUME:
133 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
134 axg_pdm_enable(priv->map);
135 return 0;
136
137 case SNDRV_PCM_TRIGGER_STOP:
138 case SNDRV_PCM_TRIGGER_SUSPEND:
139 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
140 axg_pdm_disable(priv->map);
141 return 0;
142
143 default:
144 return -EINVAL;
145 }
146 }
147
axg_pdm_get_os(struct axg_pdm * priv)148 static unsigned int axg_pdm_get_os(struct axg_pdm *priv)
149 {
150 const struct axg_pdm_filters *filters = priv->cfg->filters;
151 unsigned int os = filters->hcic.ds;
152 int i;
153
154 /*
155 * The global oversampling factor is defined by the down sampling
156 * factor applied by each filter (HCIC and LPFs)
157 */
158
159 for (i = 0; i < PDM_LPF_NUM; i++)
160 os *= filters->lpf[i].ds;
161
162 return os;
163 }
164
axg_pdm_set_sysclk(struct axg_pdm * priv,unsigned int os,unsigned int rate)165 static int axg_pdm_set_sysclk(struct axg_pdm *priv, unsigned int os,
166 unsigned int rate)
167 {
168 unsigned int sys_rate = os * 2 * rate * PDM_CHAN_CTRL_POINTER_MAX;
169
170 /*
171 * Set the default system clock rate unless it is too fast for
172 * the requested sample rate. In this case, the sample pointer
173 * counter could overflow so set a lower system clock rate
174 */
175 if (sys_rate < priv->cfg->sys_rate)
176 return clk_set_rate(priv->sysclk, sys_rate);
177
178 return clk_set_rate(priv->sysclk, priv->cfg->sys_rate);
179 }
180
axg_pdm_set_sample_pointer(struct axg_pdm * priv)181 static int axg_pdm_set_sample_pointer(struct axg_pdm *priv)
182 {
183 unsigned int spmax, sp, val;
184 int i;
185
186 /* Max sample counter value per half period of dclk */
187 spmax = DIV_ROUND_UP_ULL((u64)clk_get_rate(priv->sysclk),
188 clk_get_rate(priv->dclk) * 2);
189
190 /* Check if sysclk is not too fast - should not happen */
191 if (WARN_ON(spmax > PDM_CHAN_CTRL_POINTER_MAX))
192 return -EINVAL;
193
194 /* Capture the data when we are at 75% of the half period */
195 sp = spmax * 3 / 4;
196
197 for (i = 0, val = 0; i < PDM_CHAN_CTRL_NUM; i++)
198 val |= sp << (PDM_CHAN_CTRL_POINTER_WIDTH * i);
199
200 regmap_write(priv->map, PDM_CHAN_CTRL, val);
201 regmap_write(priv->map, PDM_CHAN_CTRL1, val);
202
203 return 0;
204 }
205
axg_pdm_set_channel_mask(struct axg_pdm * priv,unsigned int channels)206 static void axg_pdm_set_channel_mask(struct axg_pdm *priv,
207 unsigned int channels)
208 {
209 unsigned int mask = GENMASK(channels - 1, 0);
210
211 /* Put all channel in reset */
212 regmap_update_bits(priv->map, PDM_CTRL,
213 PDM_CTRL_CHAN_RSTN_MASK, 0);
214
215 /* Take the necessary channels out of reset and enable them */
216 regmap_update_bits(priv->map, PDM_CTRL,
217 PDM_CTRL_CHAN_RSTN_MASK |
218 PDM_CTRL_CHAN_EN_MASK,
219 PDM_CTRL_CHAN_RSTN(mask) |
220 PDM_CTRL_CHAN_EN(mask));
221 }
222
axg_pdm_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params,struct snd_soc_dai * dai)223 static int axg_pdm_hw_params(struct snd_pcm_substream *substream,
224 struct snd_pcm_hw_params *params,
225 struct snd_soc_dai *dai)
226 {
227 struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);
228 unsigned int os = axg_pdm_get_os(priv);
229 unsigned int rate = params_rate(params);
230 unsigned int val;
231 int ret;
232
233 switch (params_width(params)) {
234 case 24:
235 val = PDM_CTRL_OUT_MODE;
236 break;
237 case 32:
238 val = 0;
239 break;
240 default:
241 dev_err(dai->dev, "unsupported sample width\n");
242 return -EINVAL;
243 }
244
245 regmap_update_bits(priv->map, PDM_CTRL, PDM_CTRL_OUT_MODE, val);
246
247 ret = axg_pdm_set_sysclk(priv, os, rate);
248 if (ret) {
249 dev_err(dai->dev, "failed to set system clock\n");
250 return ret;
251 }
252
253 ret = clk_set_rate(priv->dclk, rate * os);
254 if (ret) {
255 dev_err(dai->dev, "failed to set dclk\n");
256 return ret;
257 }
258
259 ret = axg_pdm_set_sample_pointer(priv);
260 if (ret) {
261 dev_err(dai->dev, "invalid clock setting\n");
262 return ret;
263 }
264
265 axg_pdm_set_channel_mask(priv, params_channels(params));
266
267 return 0;
268 }
269
axg_pdm_startup(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)270 static int axg_pdm_startup(struct snd_pcm_substream *substream,
271 struct snd_soc_dai *dai)
272 {
273 struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);
274 int ret;
275
276 ret = clk_prepare_enable(priv->dclk);
277 if (ret) {
278 dev_err(dai->dev, "enabling dclk failed\n");
279 return ret;
280 }
281
282 /* Enable the filters */
283 axg_pdm_filters_enable(priv->map, true);
284
285 return ret;
286 }
287
axg_pdm_shutdown(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)288 static void axg_pdm_shutdown(struct snd_pcm_substream *substream,
289 struct snd_soc_dai *dai)
290 {
291 struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);
292
293 axg_pdm_filters_enable(priv->map, false);
294 clk_disable_unprepare(priv->dclk);
295 }
296
axg_pdm_set_hcic_ctrl(struct axg_pdm * priv)297 static void axg_pdm_set_hcic_ctrl(struct axg_pdm *priv)
298 {
299 const struct axg_pdm_hcic *hcic = &priv->cfg->filters->hcic;
300 unsigned int val;
301
302 val = PDM_HCIC_CTRL1_STAGE_NUM(hcic->steps);
303 val |= PDM_HCIC_CTRL1_DSR(hcic->ds);
304 val |= PDM_HCIC_CTRL1_GAIN_MULT(hcic->mult);
305 val |= PDM_HCIC_CTRL1_GAIN_SFT(hcic->shift);
306
307 regmap_update_bits(priv->map, PDM_HCIC_CTRL1,
308 PDM_HCIC_CTRL1_STAGE_NUM_MASK |
309 PDM_HCIC_CTRL1_DSR_MASK |
310 PDM_HCIC_CTRL1_GAIN_MULT_MASK |
311 PDM_HCIC_CTRL1_GAIN_SFT_MASK,
312 val);
313 }
314
axg_pdm_set_lpf_ctrl(struct axg_pdm * priv,unsigned int index)315 static void axg_pdm_set_lpf_ctrl(struct axg_pdm *priv, unsigned int index)
316 {
317 const struct axg_pdm_lpf *lpf = &priv->cfg->filters->lpf[index];
318 unsigned int offset = index * regmap_get_reg_stride(priv->map)
319 + PDM_F1_CTRL;
320 unsigned int val;
321
322 val = PDM_LPF_STAGE_NUM(lpf->tap_num);
323 val |= PDM_LPF_DSR(lpf->ds);
324 val |= PDM_LPF_ROUND_MODE(lpf->round_mode);
325
326 regmap_update_bits(priv->map, offset,
327 PDM_LPF_STAGE_NUM_MASK |
328 PDM_LPF_DSR_MASK |
329 PDM_LPF_ROUND_MODE_MASK,
330 val);
331 }
332
axg_pdm_set_hpf_ctrl(struct axg_pdm * priv)333 static void axg_pdm_set_hpf_ctrl(struct axg_pdm *priv)
334 {
335 const struct axg_pdm_hpf *hpf = &priv->cfg->filters->hpf;
336 unsigned int val;
337
338 val = PDM_HPF_OUT_FACTOR(hpf->out_factor);
339 val |= PDM_HPF_SFT_STEPS(hpf->steps);
340
341 regmap_update_bits(priv->map, PDM_HPF_CTRL,
342 PDM_HPF_OUT_FACTOR_MASK |
343 PDM_HPF_SFT_STEPS_MASK,
344 val);
345 }
346
axg_pdm_set_lpf_filters(struct axg_pdm * priv)347 static int axg_pdm_set_lpf_filters(struct axg_pdm *priv)
348 {
349 const struct axg_pdm_lpf *lpf = priv->cfg->filters->lpf;
350 unsigned int count = 0;
351 int i, j;
352
353 for (i = 0; i < PDM_LPF_NUM; i++)
354 count += lpf[i].tap_num;
355
356 /* Make sure the coeffs fit in the memory */
357 if (count >= PDM_LPF_MAX_STAGE)
358 return -EINVAL;
359
360 /* Set the initial APB bus register address */
361 regmap_write(priv->map, PDM_COEFF_ADDR, 0);
362
363 /* Set the tap filter values of all 3 filters */
364 for (i = 0; i < PDM_LPF_NUM; i++) {
365 axg_pdm_set_lpf_ctrl(priv, i);
366
367 for (j = 0; j < lpf[i].tap_num; j++)
368 regmap_write(priv->map, PDM_COEFF_DATA, lpf[i].tap[j]);
369 }
370
371 return 0;
372 }
373
axg_pdm_dai_probe(struct snd_soc_dai * dai)374 static int axg_pdm_dai_probe(struct snd_soc_dai *dai)
375 {
376 struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);
377 int ret;
378
379 ret = clk_prepare_enable(priv->pclk);
380 if (ret) {
381 dev_err(dai->dev, "enabling pclk failed\n");
382 return ret;
383 }
384
385 /*
386 * sysclk must be set and enabled as well to access the pdm registers
387 * Accessing the register w/o it will give a bus error.
388 */
389 ret = clk_set_rate(priv->sysclk, priv->cfg->sys_rate);
390 if (ret) {
391 dev_err(dai->dev, "setting sysclk failed\n");
392 goto err_pclk;
393 }
394
395 ret = clk_prepare_enable(priv->sysclk);
396 if (ret) {
397 dev_err(dai->dev, "enabling sysclk failed\n");
398 goto err_pclk;
399 }
400
401 /* Make sure the device is initially disabled */
402 axg_pdm_disable(priv->map);
403
404 /* Make sure filter bypass is disabled */
405 regmap_update_bits(priv->map, PDM_CTRL, PDM_CTRL_BYPASS_MODE, 0);
406
407 /* Load filter settings */
408 axg_pdm_set_hcic_ctrl(priv);
409 axg_pdm_set_hpf_ctrl(priv);
410
411 ret = axg_pdm_set_lpf_filters(priv);
412 if (ret) {
413 dev_err(dai->dev, "invalid filter configuration\n");
414 goto err_sysclk;
415 }
416
417 return 0;
418
419 err_sysclk:
420 clk_disable_unprepare(priv->sysclk);
421 err_pclk:
422 clk_disable_unprepare(priv->pclk);
423 return ret;
424 }
425
axg_pdm_dai_remove(struct snd_soc_dai * dai)426 static int axg_pdm_dai_remove(struct snd_soc_dai *dai)
427 {
428 struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);
429
430 clk_disable_unprepare(priv->sysclk);
431 clk_disable_unprepare(priv->pclk);
432
433 return 0;
434 }
435
436 static const struct snd_soc_dai_ops axg_pdm_dai_ops = {
437 .probe = axg_pdm_dai_probe,
438 .remove = axg_pdm_dai_remove,
439 .trigger = axg_pdm_trigger,
440 .hw_params = axg_pdm_hw_params,
441 .startup = axg_pdm_startup,
442 .shutdown = axg_pdm_shutdown,
443 };
444
445 static struct snd_soc_dai_driver axg_pdm_dai_drv = {
446 .name = "PDM",
447 .capture = {
448 .stream_name = "Capture",
449 .channels_min = 1,
450 .channels_max = 8,
451 .rates = SNDRV_PCM_RATE_CONTINUOUS,
452 .rate_min = 5512,
453 .rate_max = 48000,
454 .formats = (SNDRV_PCM_FMTBIT_S24_LE |
455 SNDRV_PCM_FMTBIT_S32_LE),
456 },
457 .ops = &axg_pdm_dai_ops,
458 };
459
460 static const struct snd_soc_component_driver axg_pdm_component_drv = {
461 .legacy_dai_naming = 1,
462 };
463
464 static const struct regmap_config axg_pdm_regmap_cfg = {
465 .reg_bits = 32,
466 .val_bits = 32,
467 .reg_stride = 4,
468 .max_register = PDM_STS,
469 };
470
471 static const unsigned int lpf1_default_tap[] = {
472 0x000014, 0xffffb2, 0xfffed9, 0xfffdce, 0xfffd45,
473 0xfffe32, 0x000147, 0x000645, 0x000b86, 0x000e21,
474 0x000ae3, 0x000000, 0xffeece, 0xffdca8, 0xffd212,
475 0xffd7d1, 0xfff2a7, 0x001f4c, 0x0050c2, 0x0072aa,
476 0x006ff1, 0x003c32, 0xffdc4e, 0xff6a18, 0xff0fef,
477 0xfefbaf, 0xff4c40, 0x000000, 0x00ebc8, 0x01c077,
478 0x02209e, 0x01c1a4, 0x008e60, 0xfebe52, 0xfcd690,
479 0xfb8fa5, 0xfba498, 0xfd9812, 0x0181ce, 0x06f5f3,
480 0x0d112f, 0x12a958, 0x169686, 0x18000e, 0x169686,
481 0x12a958, 0x0d112f, 0x06f5f3, 0x0181ce, 0xfd9812,
482 0xfba498, 0xfb8fa5, 0xfcd690, 0xfebe52, 0x008e60,
483 0x01c1a4, 0x02209e, 0x01c077, 0x00ebc8, 0x000000,
484 0xff4c40, 0xfefbaf, 0xff0fef, 0xff6a18, 0xffdc4e,
485 0x003c32, 0x006ff1, 0x0072aa, 0x0050c2, 0x001f4c,
486 0xfff2a7, 0xffd7d1, 0xffd212, 0xffdca8, 0xffeece,
487 0x000000, 0x000ae3, 0x000e21, 0x000b86, 0x000645,
488 0x000147, 0xfffe32, 0xfffd45, 0xfffdce, 0xfffed9,
489 0xffffb2, 0x000014,
490 };
491
492 static const unsigned int lpf2_default_tap[] = {
493 0x00050a, 0xfff004, 0x0002c1, 0x003c12, 0xffa818,
494 0xffc87d, 0x010aef, 0xff5223, 0xfebd93, 0x028f41,
495 0xff5c0e, 0xfc63f8, 0x055f81, 0x000000, 0xf478a0,
496 0x11c5e3, 0x2ea74d, 0x11c5e3, 0xf478a0, 0x000000,
497 0x055f81, 0xfc63f8, 0xff5c0e, 0x028f41, 0xfebd93,
498 0xff5223, 0x010aef, 0xffc87d, 0xffa818, 0x003c12,
499 0x0002c1, 0xfff004, 0x00050a,
500 };
501
502 static const unsigned int lpf3_default_tap[] = {
503 0x000000, 0x000081, 0x000000, 0xfffedb, 0x000000,
504 0x00022d, 0x000000, 0xfffc46, 0x000000, 0x0005f7,
505 0x000000, 0xfff6eb, 0x000000, 0x000d4e, 0x000000,
506 0xffed1e, 0x000000, 0x001a1c, 0x000000, 0xffdcb0,
507 0x000000, 0x002ede, 0x000000, 0xffc2d1, 0x000000,
508 0x004ebe, 0x000000, 0xff9beb, 0x000000, 0x007dd7,
509 0x000000, 0xff633a, 0x000000, 0x00c1d2, 0x000000,
510 0xff11d5, 0x000000, 0x012368, 0x000000, 0xfe9c45,
511 0x000000, 0x01b252, 0x000000, 0xfdebf6, 0x000000,
512 0x0290b8, 0x000000, 0xfcca0d, 0x000000, 0x041d7c,
513 0x000000, 0xfa8152, 0x000000, 0x07e9c6, 0x000000,
514 0xf28fb5, 0x000000, 0x28b216, 0x3fffde, 0x28b216,
515 0x000000, 0xf28fb5, 0x000000, 0x07e9c6, 0x000000,
516 0xfa8152, 0x000000, 0x041d7c, 0x000000, 0xfcca0d,
517 0x000000, 0x0290b8, 0x000000, 0xfdebf6, 0x000000,
518 0x01b252, 0x000000, 0xfe9c45, 0x000000, 0x012368,
519 0x000000, 0xff11d5, 0x000000, 0x00c1d2, 0x000000,
520 0xff633a, 0x000000, 0x007dd7, 0x000000, 0xff9beb,
521 0x000000, 0x004ebe, 0x000000, 0xffc2d1, 0x000000,
522 0x002ede, 0x000000, 0xffdcb0, 0x000000, 0x001a1c,
523 0x000000, 0xffed1e, 0x000000, 0x000d4e, 0x000000,
524 0xfff6eb, 0x000000, 0x0005f7, 0x000000, 0xfffc46,
525 0x000000, 0x00022d, 0x000000, 0xfffedb, 0x000000,
526 0x000081, 0x000000,
527 };
528
529 /*
530 * These values are sane defaults for the axg platform:
531 * - OS = 64
532 * - Latency = 38700 (?)
533 *
534 * TODO: There is a lot of different HCIC, LPFs and HPF configurations possible.
535 * the configuration may depend on the dmic used by the platform, the
536 * expected tradeoff between latency and quality, etc ... If/When other
537 * settings are required, we should add a fw interface to this driver to
538 * load new filter settings.
539 */
540 static const struct axg_pdm_filters axg_default_filters = {
541 .hcic = {
542 .shift = 0x15,
543 .mult = 0x80,
544 .steps = 7,
545 .ds = 8,
546 },
547 .hpf = {
548 .out_factor = 0x8000,
549 .steps = 13,
550 },
551 .lpf = {
552 [0] = {
553 .ds = 2,
554 .round_mode = 1,
555 .tap = lpf1_default_tap,
556 .tap_num = ARRAY_SIZE(lpf1_default_tap),
557 },
558 [1] = {
559 .ds = 2,
560 .round_mode = 0,
561 .tap = lpf2_default_tap,
562 .tap_num = ARRAY_SIZE(lpf2_default_tap),
563 },
564 [2] = {
565 .ds = 2,
566 .round_mode = 1,
567 .tap = lpf3_default_tap,
568 .tap_num = ARRAY_SIZE(lpf3_default_tap)
569 },
570 },
571 };
572
573 static const struct axg_pdm_cfg axg_pdm_config = {
574 .filters = &axg_default_filters,
575 .sys_rate = 250000000,
576 };
577
578 static const struct of_device_id axg_pdm_of_match[] = {
579 {
580 .compatible = "amlogic,axg-pdm",
581 .data = &axg_pdm_config,
582 }, {}
583 };
584 MODULE_DEVICE_TABLE(of, axg_pdm_of_match);
585
axg_pdm_probe(struct platform_device * pdev)586 static int axg_pdm_probe(struct platform_device *pdev)
587 {
588 struct device *dev = &pdev->dev;
589 struct axg_pdm *priv;
590 void __iomem *regs;
591
592 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
593 if (!priv)
594 return -ENOMEM;
595 platform_set_drvdata(pdev, priv);
596
597 priv->cfg = of_device_get_match_data(dev);
598 if (!priv->cfg) {
599 dev_err(dev, "failed to match device\n");
600 return -ENODEV;
601 }
602
603 regs = devm_platform_ioremap_resource(pdev, 0);
604 if (IS_ERR(regs))
605 return PTR_ERR(regs);
606
607 priv->map = devm_regmap_init_mmio(dev, regs, &axg_pdm_regmap_cfg);
608 if (IS_ERR(priv->map)) {
609 dev_err(dev, "failed to init regmap: %ld\n",
610 PTR_ERR(priv->map));
611 return PTR_ERR(priv->map);
612 }
613
614 priv->pclk = devm_clk_get(dev, "pclk");
615 if (IS_ERR(priv->pclk))
616 return dev_err_probe(dev, PTR_ERR(priv->pclk), "failed to get pclk\n");
617
618 priv->dclk = devm_clk_get(dev, "dclk");
619 if (IS_ERR(priv->dclk))
620 return dev_err_probe(dev, PTR_ERR(priv->dclk), "failed to get dclk\n");
621
622 priv->sysclk = devm_clk_get(dev, "sysclk");
623 if (IS_ERR(priv->sysclk))
624 return dev_err_probe(dev, PTR_ERR(priv->sysclk), "failed to get dclk\n");
625
626 return devm_snd_soc_register_component(dev, &axg_pdm_component_drv,
627 &axg_pdm_dai_drv, 1);
628 }
629
630 static struct platform_driver axg_pdm_pdrv = {
631 .probe = axg_pdm_probe,
632 .driver = {
633 .name = "axg-pdm",
634 .of_match_table = axg_pdm_of_match,
635 },
636 };
637 module_platform_driver(axg_pdm_pdrv);
638
639 MODULE_DESCRIPTION("Amlogic AXG PDM Input driver");
640 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
641 MODULE_LICENSE("GPL v2");
642